Python 如何解决 KeyError: u"[Index([..], dtype='object')] 都在 [columns] 中"
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How To Solve KeyError: u"None of [Index([..], dtype='object')] are in the [columns]"
提问by Tyler Joseph
I'm trying to create a SVM model from what I found in github here, but it keeps returning this error.
我正在尝试根据我在 github here 中找到的内容创建 SVM 模型，但它一直返回此错误。
Traceback (most recent call last):
File "C:\Users\Me\Documents\#e\projects\Sign-Language-Glove-master\modeling.py", line 22, in <module>
train_features = train[['F1','F2','F3','F4','F5','X','Y','Z','C1','C2']]
File "C:\Python27\lib\site-packages\pandas\core\frame.py", line 2934, in __getitem__
raise_missing=True)
File "C:\Python27\lib\site-packages\pandas\core\indexing.py", line 1354, in _convert_to_indexer
return self._get_listlike_indexer(obj, axis, **kwargs)[1]
File "C:\Python27\lib\site-packages\pandas\core\indexing.py", line 1161, in _get_listlike_indexer
raise_missing=raise_missing)
File "C:\Python27\lib\site-packages\pandas\core\indexing.py", line 1246, in _validate_read_indexer
key=key, axis=self.obj._get_axis_name(axis)))
KeyError: u"None of [Index([u'F1', u'F2', u'F3', u'F4', u'F5', u'X', u'Y', u'Z', u'C1', u'C2'], dtype='object')] are in the [columns]"
This is my code.
这是我的代码。
import pandas as pd
dataframe= pd.read_csv("lettera.csv", delimiter=',')
df=pd.DataFrame(dataframe)
from sklearn.model_selection import train_test_split
train, test = train_test_split(df, test_size = 0.2)
train_features = train[['F1','F2','F3','F4','F5','X','Y','Z','C1','C2']]
And these are the contents of the csv file.
这些是 csv 文件的内容。
LABEL, F1, F2, F3, F4, F5, X, Y, Z, C1, C2
1, 631, 761, 739, 751, 743, 14120, -5320, 7404, 0, 0
1, 632, 759, 740, 751, 744, 14108, -5276, 7444, 0, 0
1, 630, 761, 740, 752, 743, 14228, -5104, 7680, 0, 0
1, 630, 761, 738, 750, 743, 14256, -5148, 7672, 0, 0
1, 632, 759, 740, 751, 744, 14172, -5256, 7376, 0, 0
1, 632, 759, 742, 751, 746, 14288, -5512, 7412, 0, 0
1, 632, 759, 742, 751, 744, 14188, -5200, 7416, 0, 0
1, 634, 759, 738, 751, 743, 14252, -5096, 7524, 0, 0
1, 630, 759, 739, 751, 743, 14364, -5124, 7612, 0, 0
1, 630, 759, 740, 751, 744, 14192, -5316, 7424, 0, 0
1, 631, 760, 739, 752, 743, 14292, -5100, 7404, 0, 0
1, 634, 759, 738, 751, 742, 14232, -5188, 7468, 0, 0
1, 632, 759, 740, 751, 744, 14288, -5416, 7552, 0, 0
1, 630, 760, 739, 752, 743, 14344, -5072, 7816, 0, 0
1, 631, 760, 739, 752, 743, 14320, -4992, 7444, 0, 0
1, 630, 762, 739, 751, 746, 14220, -5172, 7544, 0, 0
1, 630, 759, 739, 751, 742, 14280, -5176, 7416, 0, 0
1, 630, 760, 738, 752, 740, 14360, -5028, 7468, 0, 0
1, 632, 759, 738, 752, 741, 14384, -5108, 7364, 0, 0
1, 629, 757, 737, 751, 741, 14224, -5108, 7536, 0, 0
1, 629, 758, 740, 751, 744, 14412, -5136, 7956, 0, 0
1, 629, 761, 740, 750, 744, 14468, -4868, 7100, 0, 0
1, 629, 760, 738, 752, 741, 14504, -4964, 6600, 0, 0
1, 629, 758, 738, 749, 741, 14440, -5112, 6828, 0, 0
1, 629, 760, 738, 752, 741, 14484, -5016, 7556, 0, 0
Thank you.
谢谢你。
回答by desertnaut
The problem is that there are spacesin your column names; here is what I get when I save your data and load the dataframe as you have done:
问题是您的列名中有空格；这是我保存您的数据并像您一样加载数据框时得到的结果：
df.columns
# result:
Index(['LABEL', ' F1', ' F2', ' F3', ' F4', ' F5', ' X', ' Y', ' Z', ' C1',
' C2'],
dtype='object')
so, putting back these spaces in the column names eliminates the error:
因此，在列名中放回这些空格可以消除错误：
train_features = train[[' F1',' F2',' F3',' F4',' F5',' X',' Y',' Z',' C1',' C2']] # works OK
But arguably, having spaces in your column names is notgood practice (you saw what can happen!); so it is better to eliminate them during loading. Here is the end to end code to do that (eliminating also the unnecessary second dataframe):
但可以说，在列名中包含空格并不是一个好习惯（您已经看到会发生什么！）；所以最好在加载过程中消除它们。这是执行此操作的端到端代码（还消除了不必要的第二个数据帧）：
import pandas as pd
df= pd.read_csv("lettera.csv", delimiter=',', header=None, skiprows=1, names=['LABEL','F1','F2','F3','F4','F5','X','Y','Z','C1','C2'])
from sklearn.model_selection import train_test_split
train, test = train_test_split(df, test_size = 0.2)
train_features = train[['F1','F2','F3','F4','F5','X','Y','Z','C1','C2']] # works OK
